JP5319590B2 - Copper alloy, copper alloy manufacturing method and electronic component manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a copper alloy containing titanium and a method for manufacturing an electronic component suitable for electronic component members such as connectors.

  In recent years, electronic devices typified by portable terminals and the like have been increasingly miniaturized, and accordingly, connectors used for such devices tend to have a narrow pitch and a low profile. The smaller the connector, the narrower the pin width and the smaller the folded shape, so the material used must have high strength to obtain the necessary springiness and excellent bending workability that can withstand severe bending. It is done. In this respect, a titanium-containing copper alloy (hereinafter referred to as “titanium copper”) has a relatively high strength and is most excellent in the copper alloy in terms of stress relaxation characteristics, and therefore requires a material strength. It has been used for a long time as a signal system terminal material.

  Titanium copper is an age-hardening type copper alloy. Specifically, when a supersaturated solid solution of Ti, which is a solute atom, is formed by solution treatment, and heat treatment is performed at a low temperature for a relatively long time from that state, periodic fluctuations in Ti concentration in the parent phase due to spinodal decomposition The modulation structure is developed and the strength is improved. Based on this strengthening mechanism, various methods have been studied with the aim of further improving the properties of titanium copper.

  At this time, the problem is that the strength and the bending workability are contradictory. That is, if the strength is improved, the bending workability is impaired, and conversely, if the bending workability is emphasized, a desired strength cannot be obtained.

  Therefore, by adding a third element such as Fe, Co, Ni, Si, etc. (Patent Document 1), the concentration of the impurity element group that dissolves in the matrix phase is regulated, and these are added to the second phase particles (Cu—Ti—). X-type particles) are precipitated in a predetermined distribution form to increase the regularity of the modulation structure (Patent Document 2), and the density of the trace additive elements and second-phase particles effective to refine the crystal grains is specified. From the viewpoints of (Patent Document 3) and refining crystal grains (Patent Document 4), research and development have been made to achieve both the strength and bending workability of titanium copper.

Further, in Patent Document 5, paying attention to the crystal orientation, the hot rolling conditions are adjusted to be I {420} / I ₀ {420}> 1.0 in order to prevent cracking in bending, and further cold rolling is performed. A technique has also been proposed in which strength, bending workability and stress relaxation resistance are improved by controlling the crystal orientation so as to satisfy I {220} / I ₀ {220} ≦ 3.0 by adjusting the rate. .

Japanese Patent Laid-Open No. 2004-231985 JP 2004-176163 A JP-A-2005-97638 JP 2006-283142 A JP 2008-308734 A

  The above-mentioned titanium copper is basically manufactured in the order of ingot melting casting → homogenization annealing → hot rolling → (repetition of annealing and cold rolling) → final solution treatment → cold rolling → aging treatment. .

  However, there is room for further improvement in obtaining titanium copper having more excellent characteristics. Therefore, the present invention provides a method of manufacturing a copper alloy containing titanium and an electronic component manufacturing method having excellent strength and bending workability by attempting to improve the properties of titanium copper from a viewpoint different from the conventional one. Let it be an issue.

  In the examination process for solving the above-mentioned problems, the present inventor is a method in which the order of cold rolling and aging treatment performed after the final solution treatment is reversed, that is, the order of aging treatment → cold rolling. In addition, when an attempt was made to further shorten the aging treatment time compared to the conventional method, the inventors found that the bending workability was significantly improved. That is, when the titanium copper manufactured according to the conventional procedure and the titanium copper of the present invention are compared, the titanium copper of the present invention is superior in bending workability in the case of the same strength. Further, when the bending workability is the same, the strength is excellent. In order to investigate the cause, the present inventor investigated the structure of titanium copper according to the present invention, and found characteristic points in the dislocation density and the crystal orientation developed by rolling.

  However, it is difficult to directly measure the dislocation density. This is because the dislocation distribution becomes non-uniform due to the modulation structure and the distribution of the precipitated particles. Therefore, in the present invention, the X-ray diffraction intensity (I) and the half width (β) of the {220} crystal plane in the rolled surface having a correlation with the dislocation are measured, and this measurement result is used as a reference for evaluation. Thus, the state of dislocation density was indirectly shown. The half-value width is the width (β) of the diffraction intensity curve at an intensity that is half the peak intensity (I) of the X-ray diffraction intensity curve, and is represented by 2θ.

One aspect of the present invention completed based on the above knowledge is a copper alloy for electronic parts containing 2.0 to 4.0% by mass of Ti and the balance copper and unavoidable impurities, {220 on the rolling surface. } Β {220}, which is the half width of the X-ray diffraction intensity from the crystal plane, is β ₀ {220}, which is the half width of the X-ray diffraction intensity from the {220} crystal plane of the pure copper standard powder, and the following formula: : 1.5 ≦ β {220} / β ₀ {220} ≦ 3.0, and I {220}, which is the X-ray diffraction intensity from the {220} crystal plane of the rolled surface, is a pure copper standard powder. It is a copper alloy that satisfies I ₀ {220}, which is the X-ray diffraction intensity from the {220} crystal plane, and the following formula: 4.0 ≦ I {220} / I ₀ {220} ≦ 7.0.

  In one embodiment of the copper alloy according to the present invention, one or more selected from the group consisting of Mn, Fe, Mg, Co, Ni, Cr, V, Nb, Si, B, and P as the third element In a total of 0 to 0.5 mass%.

  Another aspect of the present invention is a method for producing a copper alloy containing 2.0 to 4.0% by mass of Ti, the balance being copper and unavoidable impurities, and a material temperature of 400 after the final solution treatment. It is a manufacturing method of a copper alloy including performing cold rolling and an aging treatment in this order after performing annealing under a heating condition of 0.1 to 0.5 hours at a temperature of not lower than 500 ° C and lower than 500 ° C.

  Another aspect of the present invention is a method for producing a copper alloy for electronic parts comprising 2.0 to 4.0% by mass of Ti and the balance copper and unavoidable impurities, after the final solution treatment, It is a manufacturing method of a copper alloy including performing cold rolling and an aging treatment in this order after annealing at a material temperature of 500 ° C. or more and less than 600 ° C. under a heating condition of 0.005 to 0.01 hours.

  Another aspect of the present invention is a method for producing a copper alloy for electronic parts comprising 2.0 to 4.0% by mass of Ti and the balance copper and unavoidable impurities, after the final solution treatment, It is a manufacturing method of a copper alloy including performing cold rolling and an aging treatment in this order after annealing at a material temperature of 600 ° C. or more and less than 700 ° C. under a heating condition of 0.001 to 0.005 hours.

  In one embodiment of the production method according to the present invention, one or more selected from the group consisting of Mn, Fe, Mg, Co, Ni, Cr, V, Nb, Si, B and P as the third element. In a total of 0 to 0.5 mass%.

  In one embodiment of the manufacturing method according to the present invention, the annealing is annealing that increases the conductivity by 0.5 to 8% IACS.

  In one embodiment of the manufacturing method according to the present invention, the cold rolling workability is 10 to 30%.

  In another aspect, the present invention is a method for manufacturing an electronic component including a step of manufacturing a copper alloy by the above-described manufacturing method and a step of processing the copper alloy.

<Ti content>
If Ti is less than 2% by mass, a sufficient strengthening mechanism cannot be obtained due to the formation of a modulation structure inherent to titanium copper, and sufficient strength cannot be obtained. Conversely, if it exceeds 4% by mass, coarse TiCu ₃ precipitates. It becomes easy and there exists a tendency for intensity | strength and bending workability to deteriorate. Therefore, the content of Ti in the copper alloy according to the present invention is 2.0 to 4.0 mass%, preferably 2.7 to 3.5 mass%. Thus, by optimizing the Ti content, both strength and bending workability suitable for electronic components can be realized.

<Third element>
Since the third element contributes to the refinement of crystal grains, a predetermined third element can be added. Specifically, even if the solution treatment is performed at a high temperature at which Ti is sufficiently dissolved, the crystal grains are easily refined and the strength is easily improved. The third element also promotes the formation of the modulation structure. Furthermore, there is an effect of suppressing precipitation of TiCu ₃ . Therefore, the original age hardening ability of titanium copper can be obtained.

  In titanium copper, Fe has the highest effect. And in Mn, Mg, Co, Ni, Si, Cr, V, Nb, Mo, Zr, B, and P, the effect according to Fe can be expected, and even if added alone, the effect is seen, but two or more Multiple additions may be made.

  When these elements contain a total of 0.05% by mass or more, the effect appears. However, when the total exceeds 0.5% by mass, the solid solubility limit of Ti is narrowed and coarse second-phase particles are precipitated. It becomes easy and the strength is slightly improved, but the bending workability deteriorates. At the same time, the coarse second-phase particles promote roughening of the bent portion and promote die wear during press working. Accordingly, the total of one or more selected from the group consisting of Mn, Fe, Mg, Co, Ni, Cr, V, Nb, Mo, Zr, Si, B, and P as the third element group is 0 to 0 in total. It can contain 0.5 mass%, and it is preferable to contain 0.05-0.5 mass% in total.

  A more preferable range of these third elements is 0.17 to 0.23 mass% in Fe, and 0.15 to 0.25 mass in Co, Mg, Ni, Cr, Si, V, Nb, Mn, and Mo. %, Zr, B, and P are 0.05 to 0.5 mass%.

<X-ray diffraction intensity>
When processing such as rolling is performed, atoms slip and deform, dislocations are formed, and the matrix phase is distorted. For example, when aging and rolling after solution treatment, the parent phase is distorted by aging, and the parent phase is further distorted by subsequent cold rolling. In addition, since the influence of dislocations remains around the precipitated particles, it is further distorted. The grain boundaries are also distorted during processing. If the strain around the parent phase and the precipitated particles and the strain at the crystal grain boundaries are equal and balanced, the resistance to bending and cracking will increase. However, if the precipitated particles are coarsened at the grain boundary or weakened like a non-precipitated zone, the strain is not balanced, so that it is easily broken by bending.

  As in the conventional case, when rolling and aging after solution treatment, precipitation occurs in the large strained portion of the matrix that is distorted by rolling, so the increase in half width is mainly due to strain introduced by rolling. (Increase in half-value width).

  On the other hand, as in the copper alloy according to the present embodiment, when annealed and rolled after solution and aging, anneal before the final cold to form a modulation structure in advance and introduce appropriate lattice strain Thus, the processing strain can be controlled with an appropriate degree of rolling processing after annealing.

<Peak intensity (I) and half width (β)>
In the present invention, the peak intensity (I) and the half width of the peak (β) are used as the X-ray line intensity of the {220} crystal plane on the rolled surface as an index of dislocation density. Specifically, the titanium copper according to the present embodiment has X-ray diffraction intensity I {220} from the {220} crystal plane of the rolled surface and β {220}, which is the half width of the peak, of pure copper standard powder. X-ray diffraction intensity I ₀ {220} from the {220} crystal plane, β ₀ {220} which is the half width of the peak, and the following formula:
4 ≦ I {220} / I ₀ {220} ≦ 7,
1.5 ≦ β {220} / β ₀ {220} ≦ 3.0
Meet.
I {220}, I ₀ {220}, and β {220}, β ₀ {220} are measured under the same measurement conditions. The pure copper standard powder is defined as a copper powder having a purity of 99.5% with a 325 mesh (JIS Z8801).

In the present embodiment, I / I ₀ is preferably 4 to 7, and more preferably 4 to 6. On the other hand, β / β ₀ is preferably 1.5 to 3.0, more preferably 1.9 to 2.7. I indicates the crystal orientation, and β is affected by the local lattice spacing. The crystal rotates by rolling and I changes to the rolling orientation, but the lattice spacing of {220} changes due to precipitation and changes appear in β. The reason why the lower limit of I / I ₀ is set to 4 is to control the EC difference before and after annealing and the degree of rolling to ensure a good balance between precipitation strain and processing strain. Even if only one of the EC difference and the rolling degree is stored excessively, if the other is insufficient, the lower limit is not reached. Moreover, even if one is controlled appropriately, if an excess or deficiency occurs in the other, it falls below the lower limit. The upper limit of I / I ₀ is set to 7 in order to control the work strain and the precipitation strain in a well-balanced manner, and to prevent the strain from being accumulated excessively and impairing the bending workability. The reason why the lower limit of β / β ₀ is set to 1.5 is to control EC before and after annealing to ensure the minimum required precipitation strain, and to a structure that cannot be achieved by processing strain alone. The reason why the upper limit of β / β ₀ is set to 3.0 is that the EC before and after annealing is controlled so as not to be excessive so as to suppress the increase in precipitation strain and to suppress the bending workability.

<Application>
The copper alloy according to the present embodiment can be provided as various copper products, such as plates, strips, tubes, bars, and wires. By processing the copper alloy according to this embodiment, electronic components such as switches, connectors, jacks, terminals, and relays can be obtained.

<Manufacturing method>
One feature of the copper alloy according to the present embodiment is that after the final solution treatment, annealing is performed for a short time under a predetermined material temperature condition before cold rolling. If the temperature of the material becomes too high during annealing, the β ′ phase that does not contribute much to the strength in the subsequent aging treatment and the β phase that deteriorates the bending workability tend to precipitate. Also, if the temperature of the material during annealing is too low and too short, the development of the modulation structure caused by spinodal decomposition tends to be insufficient in the aging treatment.

  When titanium copper after solution treatment is annealed, the conductivity increases with the development of the modulation structure, so the degree of annealing can be determined by the change in conductivity before and after annealing. According to the inventor's research, it is desirable that the annealing be performed under conditions that increase the conductivity by 0.5 to 8% IACS, and preferably by 1 to 4% IACS.

Therefore, annealing is preferably performed under any of the following conditions.
Heating for 0.1 to 0.5 hours at a material temperature of 400 ° C. or more and less than 500 ° C. Heating for 0.005 to 0.01 hour as a material temperature of 500 ° C. or more and less than 600 ° C. 001 to 0.005 hours heating

In addition, annealing is more preferably performed under any of the following conditions.
-Heating at a material temperature of 500 ° C to less than 550 ° C for 0.0075 to 0.01 hours · Heating at a material temperature of 550 ° C to less than 600 ° C for 0.005 to 0.0075 hours Heat for 0025 to 0.005 hours

Hereinafter, a preferred embodiment will be described for each process.
1) Ingot manufacturing process Manufacturing of an ingot by melting and casting is basically performed in a vacuum or in an inert gas atmosphere. If the additive element remains undissolved during melting, it does not effectively act on strength improvement. Therefore, in order to eliminate undissolved residue, it is necessary to hold high-melting-point additive elements such as Fe and Cr for a certain period of time after being added and sufficiently stirred. On the other hand, since Ti is relatively easily dissolved in Cu, it may be added after the third element group is dissolved. Therefore, Cu includes one or more selected from the group consisting of Mn, Fe, Mg, Co, Ni, Cr, V, Nb, Mo, Zr, Si, B, and P in total from 0 to 0.0. It adds so that it may contain 50 mass%, and then adds Ti so that it may contain 2.0-4.0 mass%, and manufactures an ingot.

2) Homogenization annealing and hot rolling Here, it is desirable to eliminate solidified segregation and crystallized substances generated during casting as much as possible. This is because, in the subsequent solution treatment, the precipitation of the second phase particles is finely and uniformly dispersed, which is effective in preventing mixed grains. After the ingot manufacturing process, it is preferable to perform hot rolling after heating to 900 to 970 ° C. and performing homogenization annealing for 3 to 24 hours. In order to prevent liquid metal embrittlement, the temperature is preferably 960 ° C. or less before and during hot rolling.

3) First solution treatment It is then preferable to perform the solution treatment after appropriately repeating cold rolling and annealing. The reason why the solution treatment is performed in advance is to reduce the burden in the final solution treatment. That is, in the final solution treatment, it is not a heat treatment for dissolving the second phase particles, but is already in solution, so it is only necessary to cause recrystallization while maintaining that state. Just heat treatment. Specifically, the first solution treatment may be performed at a heating temperature of 850 to 900 ° C. for 2 to 10 minutes. It is preferable to increase the heating rate and cooling rate at that time as much as possible so that the second phase particles do not precipitate.

4) Intermediate rolling As the degree of processing in the intermediate rolling before the final solution treatment is increased, the second phase particles in the final solution treatment are precipitated more uniformly and finely. However, if the final solution treatment is performed with a too high degree of processing, a recrystallized texture develops and plastic anisotropy occurs, which may impair the press formability. Therefore, the processing degree of intermediate rolling is preferably 70 to 99%. The degree of work is defined by {(thickness before rolling−thickness after rolling) / thickness before rolling) × 100%}.

5) Final solution treatment In the final solution treatment, it is desirable to completely dissolve the precipitate. However, when heated to a high temperature until it completely disappears, the crystal grains become coarse, so the heating temperature is the second phase. The temperature is close to the solid solubility limit of the particle composition (the temperature at which the solid solubility limit of Ti becomes equal to the addition amount in the range of 2.0 to 4.0% by mass of Ti is 730 to 840 ° C., for example, When the addition amount of Ti is 3% by mass, it is about 800 ° C.). And if it heats rapidly to this temperature and a cooling rate is also made fast, generation | occurrence | production of coarse 2nd phase particle | grains will be suppressed. Further, the shorter the heating time at the solid solution temperature, the finer the crystal grains. Therefore, it is preferable that the material is heated for 0.5 to 3 minutes at a temperature at which the solid solubility limit of Ti at 730 to 840 ° C. is larger than the addition amount, and then cooled with water.

6) Annealing After the final solution treatment, annealing is performed. The annealing conditions are as described above.

7) Final cold rolling After the annealing, the final cold rolling is performed. The strength of titanium copper can be increased by the final cold working. At this time, if the degree of work is less than 10%, a sufficient effect cannot be obtained. However, if the working degree is too high, the working strain due to the flattening of crystal grains becomes larger than the lattice strain caused by intragranular precipitation, and the bending workability deteriorates. Furthermore, since grain boundary precipitation is likely to occur during aging treatment or strain relief annealing performed as necessary, the workability is set to 50% or less, more preferably 25% or less.

8) Aging treatment After the final cold rolling, strain annealing and aging treatment are performed as necessary. The conditions for the aging treatment may be conventional conditions, but if the aging treatment is performed lighter than in the prior art, the balance between strength and bending workability is further improved. Specifically, the aging treatment is preferably performed under the conditions of heating at a material temperature of 300 to 400 ° C. for 3 to 12 hours.

The aging treatment is more preferably performed under any of the following conditions.
・ Material temperature is 340 ° C. or more and less than 360 ° C. for 5 to 8 hours ・ Material temperature is 360 to 380 ° C. for 4 to 7 hours ・ Material temperature is 380 to 400 ° C. for 3 to 6 hours

It is even more preferable that the aging treatment is performed under any of the following conditions.
-Heat for 6 to 7 hours at a material temperature of 340 ° C to less than 360 ° C · Heat for 5 to 6 hours at a material temperature of 360 ° C to less than 380 ° C · Heat for 4 to 6 hours at a material temperature of 380 ° C to 400 ° C

  A person skilled in the art will understand that steps such as grinding, polishing, and shot blast pickling for removing oxide scale on the surface can be appropriately performed between the above steps.

  Examples of the present invention will be described below together with comparative examples, but these examples are provided for better understanding of the present invention and its advantages, and are not intended to limit the invention.

  When manufacturing the copper alloy of the present invention example, Ti, which is an active metal, is added as the second component, so a vacuum melting furnace was used for melting. In addition, in order to prevent unexpected side effects due to mixing of impurity elements other than the elements defined in the present invention, raw materials having a relatively high purity were carefully selected and used.

  Addition of the third element shown in Table 1 to Cu as required, and then add Ti at the concentration shown in Table 1 and homogenize by heating at 950 ° C. for 3 hours to the ingot having the composition of the remaining copper and inevitable impurities After annealing, hot rolling was performed at 900 to 950 ° C. to obtain a hot rolled sheet having a thickness of 10 mm. After descaling by chamfering, cold rolling was performed to obtain a strip thickness (2.0 mm), and a primary solution treatment was performed on the strip. The conditions for the primary solution treatment were heating at 850 ° C. for 10 minutes. Next, in intermediate cold rolling, the intermediate plate thickness is adjusted so that the final plate thickness is 0.10 mm, cold rolling, and then inserted into an annealing furnace capable of rapid heating, and the final solution treatment is performed. And then water cooled. The heating conditions at this time were such that the material temperature was such that the solid solubility limit of Ti was the same as the addition amount (approximately 800 ° C. at a Ti concentration of 3.2% by mass, approximately 730 ° C. at a Ti concentration of 2.0% by mass, and a Ti concentration of 5 Each sample was held for 1 minute under the heating conditions shown in Table 1 on the basis of 0.0 mass% and about 885 ° C.).

  Then, depending on the test piece, after cold rolling was performed under the conditions described in Table 1, annealing was performed in the Ar atmosphere under the conditions described in Table 1. After descaling by pickling, the final cold rolling was performed under the conditions described in Table 1, and finally aging treatment was performed under each heating condition described in Table 1, and the test pieces of Examples, Conventional Examples and Comparative Examples were did.

About each obtained test piece, characteristic evaluation was performed on the following conditions. The results are shown in Table 2.
<Strength>
A JIS No. 13B specimen was prepared using a press so that the tensile direction was parallel to the rolling direction. The specimen was subjected to a tensile test according to JIS-Z2241, and the 0.2% proof stress (YS) in the rolling parallel direction was measured.
<Bending workability>
In accordance with JIS H 3130, a W-bending test of Badway (the bending axis is the same direction as the rolling direction) was performed to measure the MBR / t value, which is the ratio of the minimum radius (MBR) to the thickness (t) at which no cracks occur.
<Conductivity>
In accordance with JIS H 0505, the conductivity (EC:% IACS) was measured by a four-terminal method.
<Crystal orientation>
For each test piece, a diffraction intensity curve of the rolled surface was obtained under the following measurement conditions using an X-ray diffractometer manufactured by Rigaku Electric Co., Ltd. model Ultima 2000, and the X-ray line intensity I {220} of the {220} crystal plane was obtained. Was measured. Under the same measurement conditions, the X-ray analysis intensity I ₀ {220} was also obtained for the pure copper powder standard sample, and I / I ₀ was calculated.
・ Target: Cu tube ・ Tube voltage: 40 kV
・ Tube current: 40 mA
・ Scanning speed: 5 ° / min
・ Sampling width: 0.02 °
<Half width>
For each test piece, a diffraction intensity curve of the rolled surface was obtained under the following measurement conditions using an X-ray diffractometer manufactured by Rigaku Electric Co., Ltd. model Ultima 2000, and the half value of the X-ray line intensity peak on the {220} crystal plane The width β {220} was measured. Under the same measurement conditions, the half-value width β ₀ {220} was also obtained for the pure copper powder standard sample, and β / β ₀ was calculated.
・ Target: Cu tube ・ Tube voltage: 40 kV
・ Tube current: 40 mA
・ Scanning speed: 5 ° / min
・ Sampling width: 0.02 °
Measurement range (2θ): 60 ° -80 °

<Discussion>
Invention Example No. According to 1-8, the copper alloy excellent in the balance of the surface of a bendability and an intensity | strength is obtained. Also, the evaluation results of I / I ₀ and β / β ₀ are good, and it can be assumed that the distortion of the crystal lattice is uniformly distributed throughout the metal structure.
On the other hand, Conventional Example 1 is an example using a conventional manufacturing method of solution treatment → rolling → aging. In Conventional Example 1, since there is no annealing before the final cold rolling, no precipitate is present, and even if the final rolling is performed at the same cold rolling degree as that of the present invention example, both precipitation strain and working strain are insufficient. However, the value of β / β ₀ was insufficient as compared with Examples 1-8. Moreover, intensity | strength was low compared with Examples 1-8.
Conventional Example 2 is an example in which the final cold rolling work degree is increased as compared with Examples 1 to 8 in the conventional manufacturing method similar to Conventional Example 1. In Conventional Example 2, by increasing the degree of work during rolling, the work strain increases and the strength increases, but the effect of work strain remains much greater than the strain due to aging precipitation, so bending workability is increased. Deteriorated. Further, since the strain due to precipitation is small, it is considered that the value of I / I ₀ is lower than those in Examples 1-8.
Comparative Example 1 is an example in which the annealing conditions were not performed under appropriate conditions (the material temperature was high and the annealing time was long) in the same manufacturing process as in the example. In Comparative Example 1, since the annealing condition is close to the solution temperature, precipitation does not proceed, the EC difference before and after annealing is small, the precipitation strain is small, and the value of β / β ₀ is insufficient compared to Examples 1-8. , Lack of strength.
In Comparative Example 2, since annealing was performed at a temperature lower than appropriate annealing conditions, precipitation was insufficient, EC difference before and after annealing was small, precipitation strain was small, and the values of I / I ₀ and β / β ₀ were implemented. Compared to Examples 1 to 8, the strength was insufficient.
The comparative example 3 shows the example whose annealing time is too long compared with Examples 1-5. In Comparative Example 3, since the degree of rolling work is appropriate, the working strain is appropriate, but the annealing time is too long and the EC difference before and after annealing becomes high, and the influence of precipitation strain becomes too large after the subsequent cold rolling and aging treatment. Since β / β ₀ increased, bending workability deteriorated.
Comparative Example 4 is an example in which the annealing time is made longer than in Examples 1 to 5 and the final cold rolling work degree is lowered. In Comparative Example 4, the effect of precipitation strain was too great and β / β ₀ was high, but I / I ₀ was low and the strength was insufficient because the workability was insufficient.
In Comparative Example 5, since the Ti concentration was too high, the amount of precipitation at the time of annealing was too high, and the EC before and after annealing was high, and the influence of the precipitation strain became too large after the subsequent cold rolling and aging treatments. _{Both 0} and β / β ₀ increased and the bending workability deteriorated.

Claims (9)

It is a copper alloy for electronic parts containing 2.0 to 4.0% by mass of Ti, consisting of the remaining copper and inevitable impurities,
Β 0 {220} which is the half width of the X-ray diffraction intensity from the {220} crystal plane of the rolled surface is β ₀ {which is the half width of the X-ray diffraction intensity from the {220} crystal plane of the pure copper standard powder. 220} and the following formula:
1.5 ≦ β {220} / β ₀ {220} ≦ 3.0
And
I {220}, which is the X-ray diffraction intensity from the {220} crystal plane of the rolled surface, is I ₀ {220}, which is the X-ray diffraction intensity from the {220} crystal plane of the pure copper standard powder, and the following formula:
4.0 ≦ I {220} / I ₀ {220} ≦ 7.0
Satisfy copper alloy.   As a third element, one or more selected from the group consisting of Mn, Fe, Mg, Co, Ni, Cr, V, Nb, Si, B and P are contained in a total amount of 0 to 0.5 mass%. The copper alloy according to claim 1. A method for producing a copper alloy containing 2.0 to 4.0% by mass of Ti and comprising the remaining copper and inevitable impurities,
After the final solution treatment, after annealing at a material temperature of 400 ° C. or more and less than 500 ° C. for 0.1 to 0.5 hours, manufacturing a copper alloy including performing cold rolling and aging treatment in order Method. A method for producing a copper alloy for electronic parts comprising 2.0 to 4.0% by mass of Ti, the balance being copper and inevitable impurities,
After the final solution treatment, after annealing at a material temperature of 500 ° C. or more and less than 600 ° C. under a heating condition of 0.005 to 0.01 hours, manufacturing of a copper alloy including sequentially performing cold rolling and aging treatment Method. A method for producing a copper alloy for electronic parts comprising 2.0 to 4.0% by mass of Ti, the balance being copper and inevitable impurities,
After the final solution treatment, after annealing at a material temperature of 600 ° C. or more and less than 700 ° C. under a heating condition of 0.001 to 0.005 hours, manufacturing of a copper alloy including sequentially performing cold rolling and aging treatment Method.   As a third element, one or more selected from the group consisting of Mn, Fe, Mg, Co, Ni, Cr, V, Nb, Si, B and P are contained in a total amount of 0 to 0.5 mass%. The manufacturing method of the copper alloy of any one of Claims 3-5.   The method for producing a copper alloy according to any one of claims 3 to 6, wherein the annealing is annealing that raises the conductivity by 0.5 to 8% IACS.   The method for producing a copper alloy according to any one of claims 3 to 7, wherein a workability of the cold rolling is 10 to 30%.   The manufacturing method of an electronic component including the process of manufacturing a copper alloy with the manufacturing method of any one of Claims 3-8, and the process of processing the said copper alloy.